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I'm trying to push an item to an array every 5 seconds in an AngularJS service, but I keep getting 'items is not defined' after 1 item is added dynamically...

I've been playing with this simple code for over an hour now, I'm sure it's something silly but I can't figure it out. :/

app.service('ItemService', function() {
  var items = [9000];
  this.addItem = function () {
    items.push(Math.random());
  setInterval(this.addItem(), 5000);
  return {
    get: function() {
      return items;
Plnkr: http://plnkr.co/edit/EVFUww7dfUAJzQqth7mx
                @SearchAndResQ - It isn't wrong - It creates an array with one item at index:0 with value 9000.
– techfoobar
                Feb 17, 2015 at 8:54
You're using angular, so you shouldn't be doing setInterval, but rather use the $interval service provided by Angular.
That, coupled with the correct observation of @techfoobar, would result in the correct behavior you are looking for:
app.service('ItemService', ['$interval', function($interval) {
  var items = [9000];
  this.addItem = function () {
    items.push(Math.random());
  $interval(this.addItem, 5000); 
  return {
    get: function() {
      return items;
Working Plunker.
You are calling addItem() and passing its return value to setInterval() - instead of the function itself.
It should be:
setInterval(this.addItem, 5000); // no () after addItem
Timing function like window.setInterval, in angularjs are wrapped in $interval (https://docs.angularjs.org/api/ng/service/$interval).
Angular manages interval function like a promise to ensure more control over timer.
        
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